Optical device and organic EL display

Abstract

An optical device includes a first waveguide layer in which multiple-beam interference occurs, a second wavelength layer which includes a back surface facing the first waveguide layer and a front surface as a light output surface, and an outcoupling layer which is disposed on a back side of the second waveguide layer and faces the first wave guide layer, wherein the outcoupling layer includes a first portion as a layer with light transmission property and second portions which are dispersed in the first portion and differ in optical property from the first portion, and wherein an array of the second portions forms a triangular lattice.

1. An organic EL display comprising:
 an organic EL element which comprises a front electrode, a back electrode facing the front electrode, and an organic layer interposed between the front and back electrodes and including an emitting layer; 
 a thin-film transistor; 
 a source electrode connected to a source of the thin-film transistor; 
 a drain electrode connected between a drain of the thin-film transistor and one of the front and back electrodes; 
 an insulating layer with light transmission property which comprises a back surface facing the front electrode and a front surface as a light output surface; and 
 an outcoupling layer which is disposed on a back side of the insulating layer, faces the organic EL element, overlies the source and drain electrodes, and is provided with a through-hole through which the front or back electrode is connected to the drain electrode, 
 wherein the outcoupling layer comprises a first portion as a layer with light transmission property and second portions which are dispersed in the first portion and differ in optical property from the first portion, and wherein an array of the second portions forms a triangular lattice. 
 
     
     
       2. The display according to  claim 1 , wherein each of the second portions is substantially circular when viewed from a direction perpendicular to a main surface of the outcoupling layer. 
     
     
       3. The display according to  claim 1 , wherein the first portion is provided with apertures, and wherein the apertures are filled with the second portions, respectively. 
     
     
       4. The display according to  claim 1 , wherein the second portions differ in refractive index from the first portion. 
     
     
       5. The display according to  claim 1 , wherein the outcoupling layer is interposed between the insulating layer and the front electrode. 
     
     
       6. The display according to  claim 1 , further comprising a reflecting layer disposed on a back side of the back electrode, wherein the back electrode has light transmission property. 
     
     
       7. The display according to  claim 6 , wherein the outcoupling layer is interposed between the back electrode and the reflecting layer. 
     
     
       8. The display according to  claim 1 , wherein the insulating layer includes a transparent substrate. 
     
     
       9. The display according to  claim 1 , wherein the insulating layer includes a transparent protective layer. 
     
     
       10. The display according to  claim 1 , wherein a surface of the outcoupling layer which faces the organic EL element is flat. 
     
     
       11. The display according to  claim 1 , wherein the outcoupling layer is configured to enhance directivity of light output from the front surface of the insulating layer. 
     
     
       12. The display according to  claim 1 , wherein each of the second portions has a columnar shape. 
     
     
       13. An organic EL display comprising:
 an organic EL element which comprises a front electrode, a back electrode facing the front electrode, and an organic layer interposed between the front and back electrodes and includes an emitting layer; 
 a thin-film transistor; 
 a source electrode connected to a source of the thin-film transistor; 
 a drain electrode connected between a drain of the thin-film transistor and one of the front and back electrodes; 
 an insulating layer with light transmission property which comprises a back surface facing the front electrode and a front surface as a light output surface; and 
 an outcoupling layer which is disposed on a back side of the insulating layer, faces the organic EL element, overlies the source and drain electrodes, and is provided with a through-hole through which the front or back electrode is connected to the drain electrode, 
 wherein the outcoupling layer comprises a first portion as a layer with light transmission property and second portions which differ in optical property from the first portion. 
 
     
     
       14. The display according to  claim 13 , wherein the outcoupling layer is configured to enhance directivity of light output from the front surface of the insulating layer. 
     
     
       15. The display according to  claim 13 , wherein each of the second portions has a columnar shape.